System information

20 Chapter 1 Introducing Mac OS X Server
Users with Mac OS X Snow Leopard or Leopard use Time Machine to back up their
Macs to an external hard drive (not shown) attached to the server.
Some users have their portable computers and home computers set up to connect to
the server’s VPN via the Internet. This gives them secure remote access, while traveling
or working at home, to all the services that the server provides on the local network.
iPhone users check wikis and blogs while they’re roaming.
Single Server with a Network Router
The next illustration shows Mac OS X Server and users’ computers and iPhones sharing
an Internet connection through a wireless router from the ISP.
The wireless router in this conguration takes the place of the AirPort Extreme Base
Station in the previous conguration. The wireless router has a built-in DSL or cable
modem that connects to the Internet. The router has wired and wireless connections
to the local network to provide Internet access to the server and users’ computers and
iPhones. The router includes a DHCP server that provides network addresses to the
server and to the users’ computers and iPhones.
In this conguration, the server’s rewall blocks malicious attacks originating outside
the local network. The rewall is congured to allow some services to receive incoming
communications. For example, iChat service can receive instant messaging invitations
from Google Talk users via the Internet.